The refrigeration industry has been working for the past few decades to find replacement refrigerants for the ozone depleting chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) being phased out as a result of the Montreal Protocol. The solution for most refrigerant producers has been the commercialization of hydrofluorocarbon (HFC) refrigerants. The new HFC refrigerants, including HFC-134a, have zero ozone depletion potential and thus are not affected by the current regulatory phase out as a result of the Montreal Protocol.
Further environmental regulations may ultimately cause global phase out of certain HFC refrigerants. Currently, industry is facing regulations relating to global warming potential (GWP) for refrigerants used in mobile air conditioning. Should the regulations be more broadly applied in the future, for instance for stationary air conditioning and refrigeration systems, an even greater need will be felt for refrigerants that can be used in all areas of the refrigeration and air-conditioning industry. In order to achieve low GWP, hydrofluorocarbon and hydrocarbon refrigerants with various levels of flammability have been proposed
Refrigerant systems, such as air conditioning, refrigeration or heat pump systems, using flammable refrigerants may leak or otherwise escape from the refrigerant container or tubing due to vehicle accident or system malfunction. When the refrigerants are exposed to potential ignition sources, such as those within an automobile engine compartment, the potential for fire is present. For example, in the event that the refrigerant lines or containers are cut, punctured, ruptured, or otherwise damaged, such as in an automobile accident, the flammable refrigerants may contact certain ignition sources and thus lead to a fire. Systems are needed to prevent ignition of refrigerants and to otherwise mitigate the spread of a fire to other nearby combustible materials that may further damage property or materials within the vicinity of the ignition or be a risk to passengers.